Combined punching and fixing device for saw blades in saw frames



Dec. 5, 1944. B. J. BRUNZELL 7 COMBINED PUNCHING AND FIXING DEVICE FOR SAWBLADES IN SAW FRAMES Filed Sept. 25, 1943 P 7 4- l A AA Int/(2231601 l3. c1131 01226 ll Z/ZM/W yM iii/5,

Patented Dec. 5, 1944 COMBINED PUNCHING AND FIXING DEVICE FOR SAW BLADES IN SAW FRAMES Bror Johan Brunzell, Viksjofors, Sweden Application September 23, 1943, Serial No. 503,563

In Sweden February 26, 1942 1 Claim. (01. 164i19) The present invention relates to a combined punching and fixing device for sawblades in saw frames. The invention is substantially characterized by the fact that the device consists of three superimposed oblong plates which at one end are fixed to one another and provided with a through-hole, while their other free ends are somewhat separated from one another due to the elasticity of the outer plates, one of the outer plates being at its free end provided with a punch adapted to freely traverse a holein the middle plate and partly project into a similar hole in the other outer plate, the fixing device being adapted to be used as hole punching device for the sawblade as well as connecting member between the sawblade and the saw frame.

An embodiment of the invention is illustrated by way of example on the accompanying drawing.

Fig. 1 shows a top view of the fixing device with a sawblade to be punched being indicated by dots.

Fig. 2 shows a side view of the device with a sawblade indicated by dots.

Fig. 3 shows part of a saw frame which is connected with the sawblade by means of the fixing device according to the invention.

The reference numerals I, 2 and 3 indicate the plates forming the fixing device. The plates are preferably of steel and superimposed one upon the other. In one end they are connected by means of riveting, spot welding or the like. At the same end there is a through-hole 4 in order to fix the device to the saw frame. ends of the plates are somewhat separated from one another due to the elasticity of the plates 4 and 3. The plate I is provided with a punch 5 of hardened steel, said punch being provided with a punch head 6. The punch is adapted to go through a hole 1 of the middle plate 2 and to partly project into a hole 8 of the lower plate 3. The hole 8 is extended at its outward directed edge in order to prevent the punched piece from sticking fast to the hole. At punching the plate 2 serves as pressing plate and the plate 3 as sup port. The fixingdevice is used in the following manner. If the sawblade has burst at the fixing hole, which often is the case, the device is placed on a hard support, for example an axe hammer,

The free I a stub or the like if the work is performed in the 7 wood. Then the sawblade is inserted between the plates 2 and 3, as shown in Figs. 1 and 2, and by a light blow on the punch a new hole is obtained at the desired place. Due to the resilience of the plates the punch is liberated from the sawblade, and the latter is immediately ready to be mounted to the saw frame which is made by the same punch device. The sawblade is inserted between the plates I and 2 by the same being separated a little, whereafter due to the elasticity the punch enters the new hole and serves as a bearing pin for the sawblade. The other end of the fixing device is inserted in the saw frame where it is secured by a locking pin through the hole 4, as is clear from Fig. 3, and then the saw can be used again.

The simple device here described is very practical and valuable, particularly for forest workmen. If necessary, a new hole can be made in a sawblade immediately at the place of work without any extra auxiliary means whatsoever,

and the saw can work again without any considerable loss of time. Earlier one had to go to a workshop and the sawblade had to be annealed in one end if the hole were to be bored, which always causes a great loss of time. Morever, the

device according to the invention is cheap to" punch adapted to freely traverse a hole in the middle plate and partly project into a similar hole in the other outer plate, the fixing device being adapted to be used as hole punching device for the sawblade as well as connecting member between the sawblade and the saw frame.

BROR JOHAN BRUNZELL. 

